Greetings!
I have a 1994 E500 (and also a ‘94 E420); however, this question concerns the 500E).
Background: My 500E is very clean and has been well cared for by the previous owner, who was also the original owner of the car. The car has been a Florida car it’s entire life, is completely rust-free, and has 149k miles on the clock. I purchased the car about a year ago, and it has been completely trouble-free until recently. After purchasing the car, I changed all the fluids, filters and plugs. It appears that the engine wiring harness was replaced at some point by the previous owner.
Start of the Problem: A few months ago when I started the car for the first time after sitting for a few weeks, it began to hesitate whenever I would apply the throttle. Once the car was moving, I didn’t notice anything abnormal, but when starting from a stop, it would accelerate extremely slowly, even when pushing the gas all the way down. I was hoping that it only required a simple fix, and put some fuel water eliminator in the tank, which seemed to fix the problem.
About a week later, the car again began to hesitate upon acceleration, right after starting the car; albeit much worse this time. It stalled several times while merely reversing out of the garage. During this time, the ASR light came on, but not the Check Engine.
I was able to limp it to my repair shop, who are experienced with these cars and others. Since being at the shop, I had all the vacuum lines replaced (the logic being to start with what’s easiest). This didn’t improve the problem, and now the car was having difficulty starting, running very roughly, and backfiring. Once the car would start, it would idle at very low RPMs, and had almost no power. As the engine temp would increase, the problem became even worse to the point that it would refuse to start once warm, and I’d have to wait for it to cool before starting it again.
I proceeded to replace all of the control modules including the: 1) Basic CM, 2) ASR CM, 3) Throttle Control Unit (EGas), and 4) Engine Control Unit. None of these resulted in any improvement.
Now the car will not start at all and it appears to have very low fuel pressure in the rail. I cannot hear the fuel pump engage before or while cranking. I pulled the fuel pump relay and it appears good, but I’ll replace this before proceeding to replace the fuel pump and filter.
If anyone has any suggestions on how I should proceed, I’d appreciate it so very much. Thank you in advance!
I have a 1994 E500 (and also a ‘94 E420); however, this question concerns the 500E).
Background: My 500E is very clean and has been well cared for by the previous owner, who was also the original owner of the car. The car has been a Florida car it’s entire life, is completely rust-free, and has 149k miles on the clock. I purchased the car about a year ago, and it has been completely trouble-free until recently. After purchasing the car, I changed all the fluids, filters and plugs. It appears that the engine wiring harness was replaced at some point by the previous owner.
Start of the Problem: A few months ago when I started the car for the first time after sitting for a few weeks, it began to hesitate whenever I would apply the throttle. Once the car was moving, I didn’t notice anything abnormal, but when starting from a stop, it would accelerate extremely slowly, even when pushing the gas all the way down. I was hoping that it only required a simple fix, and put some fuel water eliminator in the tank, which seemed to fix the problem.
About a week later, the car again began to hesitate upon acceleration, right after starting the car; albeit much worse this time. It stalled several times while merely reversing out of the garage. During this time, the ASR light came on, but not the Check Engine.
I was able to limp it to my repair shop, who are experienced with these cars and others. Since being at the shop, I had all the vacuum lines replaced (the logic being to start with what’s easiest). This didn’t improve the problem, and now the car was having difficulty starting, running very roughly, and backfiring. Once the car would start, it would idle at very low RPMs, and had almost no power. As the engine temp would increase, the problem became even worse to the point that it would refuse to start once warm, and I’d have to wait for it to cool before starting it again.
I proceeded to replace all of the control modules including the: 1) Basic CM, 2) ASR CM, 3) Throttle Control Unit (EGas), and 4) Engine Control Unit. None of these resulted in any improvement.
Now the car will not start at all and it appears to have very low fuel pressure in the rail. I cannot hear the fuel pump engage before or while cranking. I pulled the fuel pump relay and it appears good, but I’ll replace this before proceeding to replace the fuel pump and filter.
If anyone has any suggestions on how I should proceed, I’d appreciate it so very much. Thank you in advance!
